A nomogram clinical prediction model for predicting urinary infection stones: development and validation in a retrospective study.

PURPOSE: This study aimed to develop a nomogram prediction model to predict the exact probability of urinary infection stones before surgery in order to better deal with the clinical problems caused by infection stones and take effective treatment measures. METHODS: We retrospectively collected the clinical data of 390 patients who were diagnosed with urinary calculi by imaging examination and underwent postoperative stone analysis between August 2018 and August 2023. The patients were randomly divided into training group (n = 312) and validation group (n = 78) using the "caret" R package. The clinical data of the patients were evaluated. Univariate and multivariate logistic regression analysis were used to screen out the independent influencing factors and construct a nomogram prediction model. The receiver operating characteristic curve (ROC), calibration curves, and decision curve analysis (DCA) and clinical impact curves were used to evaluate the discrimination, accuracy, and clinical application efficacy of the prediction model. RESULTS: Gender, recurrence stones, blood uric acid value, urine pH, and urine bacterial culture (P < 0.05) were independent predictors of infection stones, and a nomogram prediction model ( https://zhaoyshenjh.shinyapps.io/DynNomInfectionStone/ ) was constructed using these five parameters. The area under the ROC curve of the training group was 0.901, 95% confidence interval (CI) (0.865-0.936), and the area under the ROC curve of the validation group was 0.960, 95% CI (0.921-0.998). The results of the calibration curve for the training group showed a mean absolute error of 0.015 and the Hosmer-Lemeshow test P > 0.05. DCA and clinical impact curves showed that when the threshold probability value of the model was between 0.01 and 0.85, it had the maximum net clinical benefit. CONCLUSIONS: The nomogram developed in this study has good clinical predictive value and clinical application efficiency can help with risk assessment and decision-making for infection stones in diagnosing and treating urolithiasis.

Establishment and application of a nomogram diagram for predicting calcium oxalate stones in patients with urinary tract stones.

This retrospective study aims to examine the correlation between calcium oxalate (CaOx) stones and common clinical tests, as well as urine ionic composition. Additionally, we aim to develop and implement a personalized model to assess the accuracy and feasibility of using charts to predict calcium oxalate stones in patients with urinary tract stones. A retrospective analysis was conducted on data from 960 patients who underwent surgery for urinary stones at the First Affiliated Hospital of Soochow University from January 1, 2010, to December 31, 2022. Among these patients, 447 were selected for further analysis based on screening criteria. Multivariate logistic regression analysis was then performed to identify the best predictive features for calcium oxalate stones from the clinical data of the selected patients. A prediction model was developed using these features and presented in the form of a nomogram graph. The performance of the prediction model was assessed using the C-index, calibration curve, and decision curve, which evaluated its discriminative power, calibration, and clinical utility, respectively. The nomogram diagram prediction model developed in this study is effective in predicting calcium oxalate stones which is helpful in screening and early identification of high-risk patients with calcium oxalate urinary tract stones, and may be a guide for urologists in making clinical treatment decisions.

Mixed stones: urinary stone composition, frequency and distribution by gender and age.

Proper analysis of urinary stone composition is a cornerstone for diagnosis, targeted treatment and recurrence prevention of urolithiasis. The aim of this study was to determine the composition, frequency and distribution of mixed stones according to gender and age of patients. A total of 42,519 urinary stones from 30,311 men and 12,208 women submitted between January 2007 and December 2020 were studied. Most urinary calculi consisted of two components (50.9%), followed by stones of a single constituent (27.1%) and three-component stones (21.9%), while four-component stones were only rarely identified (0.1%). Among all stones, 49.8% consisted of whewellite (COM), weddellite (COD), and mixtures of COM and COD, 33.8% were pure carbonate apatite (CA) and mixtures of CA with COM and/or COD, while 7.6% were composed of uric acid anhydrous (UAA), uric acid dihydrate (UAD), and mixed UAA and UAD. The remaining 8.8% of calculi were rare single-component stones and rare mixtures of various constituents. The number of stone components was inversely associated with age (p < 0.001). The proportion of men decreased significantly with the number of stone constituents, from 3.01:1 for single-component stones to 1.0:1 for four-component urinary calculi (p < 0.001). The vast majority of urinary calculi consisted of two or more components in varying proportions. While age was inversely associated with the number of stone constituents, the proportion of women increased significantly from single-component to four-component urinary calculi. A significant proportion of mixed stones could present a challenge for diagnosis and targeted recurrence prevention.

Raised CK and acute kidney injury following intense exercise in three patients with a history of exercise intolerance due to homozygous mutations in SLC2A9.

Acute rhabdomyolysis (AR) leading to acute kidney injury has many underlying etiologies, however, when the primary trigger is exercise, the most usual underlying cause is either a genetic muscle disorder or unaccustomed intense exercise in a healthy individual. Three adult men presented with a history of exercise intolerance and episodes of acute renal impairment following intense exercise, thought to be due to AR in the case of two, and dehydration in one. The baseline serum CK was mildly raised between attacks in all three patients and acutely raised during attacks in two of the three patients. Following referral to a specialized neuromuscular centre, further investigation identified very low serum urate (<12 umol/L). In all three men, genetic studies confirmed homozygous mutations in SLC2A9, which encodes for facilitated glucose transporter member 9 (GLUT9), a major regulator of urate homeostasis. Hereditary hypouricaemia should be considered in people presenting with acute kidney injury related to intense exercise. Serum urate evaluation is a useful screening test best undertaken after recovery.

Consideration of Comparing Empirical and Evidence-Based Knowledge on Nephrology in the Example of Ahi Çelebi's Fifteenth Century Turkish Treatise on the Urinary Calculus.

The objective of the study is to discuss the question, "how did physicians come to grasp some facts in the absence of scientific experimentation and medical technology?" within the framework of examples from Ahi? Ahmed Çelebi's fifteenth century Turkish treatise on the urinary calculus. Çelebi's monograph on the urinary calculus in the kidneys and the bladder written in Turkish in Arabic alphabet is transliterated and studied within the framework of the medical theory of the period. The sample information for this study was randomly chosen. Examples of epidemiological information, diets against urinary calculus formation, diagnoses of kidney and urinary bladder calculi, and symptomatic therapies noted in Çelebi's treatise are discussed, with results briefly compared with today's data. The study of Çelebi's treatise shows that it was possible to reach some medical facts with the methods of the period.

Atypical clinical presentation and management of urinary stone disease in non-verbal non-ambulatory children.

INTRODUCTION: Management of kidney stones primarily depends on various factors such as the presence of urinary tract obstruction, pain, stone size, location, impact on renal function, and the existence of infection. Renal colic is the classic presentation of an obstructive kidney stone. However, in this study, we present a cohort of non-verbal non-ambulatory (NVNA) patients who exhibit a distinct and uncommon presentation of kidney stones due to their medical conditions. Information about kidney stone disease in this gropup of complex pediatric patients is, scarce and their associated risk factors are not well understood. Therefore, we aim to summarize the clinical presentation, and management challenges in this unique group of NVNA patients to identify potential variables for prospective studies. METHODS: A retrospective chart review was completed for all NVNA patients seen at the pediatric multidisciplinary kidney stone clinic between July 2020 to August 2022. Demographic variables, clinical presentation data, metabolic evaluation, radiological imaging, and surgical management was included for analysis. RESULTS: A total of 224 pediatric patients were referred to the multidisciplinary stone clinic. Of those, 27 were identified to be NVNA. The most common primary diagnosis was Cerebral Palsy followed by Lennox-Gastaut syndrome. Average age at first kidney stone presentation was 11.5 years ± 5.7 years. An obstructing stone was diagnosed in 18 (66%) patients, 4 (22.2%) of these presented with sepsis. Average stone burden was 9.2 mm ( ± 5.8 mm). Of the obstructing stones, 13 (72%) were in the kidney. All patients with an obstructing stone underwent surgical management with retrograde endoscopic approach. Metabolic 24-h-urine analysis was completed in 24 (89%) patients. 17 (62%) had an elevated urine density, 15 (55%) demonstrated calcium oxalate supersaturation, 12 (44%) met criteria for acidosis, and 7 (26%) had significant hypocitraturia. DISCUSSION: NVNA patients represent a unique cohort whose clinical presentation is atypical. Limited ability to express symptoms makes early detection difficult to recognize. Twenty two percent of patients present with sepsis as their first manifestation of an acutely obstructing kidney stone. Pain is subjectively interpreted by caregivers and is an uncommon symptom. Our cohort demonstrates common risk factors for stones including propensity for chronic dehydration, slow urinary tract transit, ineffective bladder emptying, G-tube feeding, and lithogenic medications. CONCLUSION: NVNA pediatric patients have atypical kidney stone clinical presentation. Awareness of this unique group of patients should support future collaborative studies to focus on understanding these atypical presentations and reflect on improving management.

A retrospective study using machine learning to develop predictive model to identify urinary infection stones in vivo.

Preoperative diagnosis of urinary infection stones is difficult, and accurate detection of stone composition can only be performed ex vivo. To provide guidance for better perioperative management and postoperative prevention of infection stones, we developed a machine learning model for preoperative identification of infection stones in vivo. The clinical data of patients with urolithiasis who underwent surgery in our hospital from January 2011 to December 2015 and January 2017 to December 2021 were retrospectively analyzed. A total of 2565 patients were included in the study, and 1168 eligible patients with urinary calculi were randomly divided into training set (70%) and test set (30%). Five machine learning algorithms (Support Vector Machine (SVM), Multilayer Perceptron (MLP), Decision Tree (DT), Random Forest Classifier (RFC), and Adaptive Boost (AdaBoost)) and 14 preoperative variables were used to construct the prediction model. The performance measure was the area under the receiver operating characteristic curve (AUC) of the validation set. The importance of 14 features in each prediction model for predicting infection stones was analyzed. A total of 89 patients (5.34%) with infection stones were included in the validation set. All the five prediction models showed strong discrimination in the validation set (AUC: 0.689-0.772). AdaBoost model was selected as the final model (AUC: 0.772(95% confidence interval, 0.657-0.887); Sensitivity: 0.522; Specificity: 0.902), UC positivity, and urine pH value were two important predictors of infection stones. We developed a predictive model through machine learning that can quickly identify infection stones in vivo with good predictive performance. It can be used for risk assessment and decision support of infection stones, optimize the disease management of urinary calculi and improve the prognosis of patients.

Specialist Care, Metabolic Testing, and Testing Completeness Among U.S. Veterans with Urinary Stone Disease.

Purpose: Recent observational studies reporting a lack of benefit from 24-hour urine testing for urinary stone disease (USD) prevention assumed testing included all components recommended from clinical guidelines. We sought to assess the completeness of 24-hour urine testing in the VA population. Materials and methods: From the VHA Corporate Data Warehouse (2012-2019), we identified patients with USD (n=198,621) and determined those who saw a urologist and/or nephrologist, and received 24-hour urine testing within 12 months of their index USD encounter. Through Logical Observation Identifiers Names and Codes, we evaluated each collection's completeness, defined as including all of urine volume, calcium, oxalate, citrate, uric acid, and creatinine. We then fit a multilevel logistic regression model with random effects for VHA facility to evaluate factors associated with specialist follow-up, testing, and testing completeness. Results: Specialist follow-up occurred in 54.3% and was stable over time. Testing occurred in 8.4%, declining from 9.3% in 2012 to 7.2% in 2019. Of tests performed, 54.6% were complete (43.7% increasing to 62.7% from 2012-2019). In adjusted analysis, there was high between-facility variation in specialist follow-up (median OR 2.0; 95% CI 1.7-2.0), testing (median OR 2.2, 95% CI 1.9-2.4), and testing completeness (median OR, 6.0, 95% CI 4.5-7.3). Individual facilities contributed 52% (intraclass correlation coefficient, 0.52; 95% CI, 0.44-0.57) towards the observed variation in testing completeness. Conclusions: Approximately 1 in 12 U.S. Veterans with USD receive metabolic testing and half of these tests are complete. Addressing facility level variation in testing completeness may improve USD care.

[Endoscopic papillary abnormalities and urinary stone recognition (EPSR): How and why?] / Reconnaissance endoscopique des anomalies papillaires et des calculs urinaires (REPC) : comment et quel intérêt ?

INTRODUCTION: The purpose of this article is to present the endoscopic papillary abnormalities and stone recognition (EPSR) to state-certified nurses (IDE and IBODE) working in the operating room. METHODS: This article is based on a literature review and the author's experience concerning the endoscopic papillary abnormalities and stone recognition. RESULTS: Since the advent of minimally invasive surgery and the laser, stones are no longer sent as one piece to laboratories, but fragmented. This has made it more difficult for biologists to fully analyze the stones, because they have less morphological data than before. Therefore, endoscopic papillary abnormalities and stone recognition have positioned themselves as tools that can compensate for this loss of information. They play a pivotal role in the identification of the lithogenesis cause, and thus allow a recurrence risk reduction of stones. CONCLUSION: Endoscopic papillary abnormalities and stone recognition are recent tools that require learning. However, the benefit of their uses is proven and is necessary for a complete management of urolithiasis.

Male Urethral Diverticulum with Stones Presenting as Acute Urinary Retention.

The urethral diverticulum is an outpouching of the urethral wall communicating with its lumen. Acquired male urethral diverticulum is a rare entity and arises secondary to intervention or distal urethral obstruction. Most patients present with lower urinary tract symptoms (LUTS). Development of calculi is seen in 4-10% of cases. We describe a case of a 63-year gentleman who presented with urinary tract infection (UTI) and acute urinary retention (AUR). He denied history of urolithiasis. Per-urethral catheterization failed, so a supra-pubic catheter was placed and UTI was managed with broad-spectrum parenteral antibiotics. On workup, he was found to have a large tubular urethral diverticulum in the anterior urethra with multiple stones and urethral strictures. The case was managed endoscopically with optical urethrotomy and fragmentation and retrieval of stones using a semi-rigid ureteroscope and pneumatic lithoclast. Key Words: Urethra, Diverticulum, Male, urethral calculus, Lithoclast.

How Reliable Is Endoscopic Stone Recognition? A Comparison Between Visual Stone Identification and Formal Stone Analysis.

Objective: To assess the diagnostic accuracy and intra-observer agreement of endoscopic stone recognition (ESR) compared with formal stone analysis. Introduction: Stone analysis is a corner stone in the prevention of stone recurrence. Although X-ray diffraction (XRD) and infrared spectroscopy are the recommended techniques for reliable formal stone analysis, this is not always possible, and the process takes time and is costly. ESR could be an alternative, as it would give immediate information on stone composition. Materials and Methods: Fifteen endourologists predicted stone composition based on 100 videos from ureterorenoscopy. Diagnostic accuracy was evaluated by comparing the prediction from visual assessment with stone analysis by XRD. After 30 days, the videos were reviewed again in a random order to assess intra-observer agreement. Results: The median diagnostic accuracy for calcium oxalate monohydrate was 54% in questionnaire 1 (Q1) and 59% in questionnaire 2 (Q2), whereas calcium oxalate dihydrate had a median diagnostic accuracy of 75% in Q1 and 50% in Q2. The diagnostic accuracy for calcium hydroxyphosphate was 10% in Q1 and 13% in Q2. The median diagnostic accuracy for calcium hydrogen phosphate dihydrate and calcium magnesium phosphate was 0% in both questionnaires. The median diagnostic accuracy for magnesium ammonium phosphate was 20% in Q1 and 40% in Q2. The median diagnostic accuracy for uric acid was 22% in both questionnaires. Finally, there was a diagnostic accuracy of 60% in Q1 and 80% in Q2 for cystine. The intra-observer agreement ranged between 45% and 72%. Conclusion: Diagnostic accuracy of ESR is limited and intra-observer agreement is below the threshold of acceptable agreement.

Evaluation and understanding of automated urinary stone recognition methods.

OBJECTIVE: To assess the potential of automated machine-learning methods for recognizing urinary stones in endoscopy. MATERIALS AND METHODS: Surface and section images of 123 urinary calculi (109 ex vivo and 14 in vivo stones) were acquired using ureteroscopes. The stones were more than 85% 'pure'. Six classes of urolithiasis were represented: Groups I (calcium oxalate monohydrate, whewellite), II (calcium oxalate dihydrate, weddellite), III (uric acid), IV (brushite and struvite stones), and V (cystine). The automated stone recognition methods that were developed for this study followed two types of approach: shallow classification methods and deep-learning-based methods. Their sensitivity, specificity and positive predictive value (PPV) were evaluated by simultaneously using stone surface and section images to classify them into one of the main morphological groups (subgroups were not considered in this study). RESULTS: Using shallow methods (based on texture and colour criteria), relatively high sensitivity, specificity and PPV for the six classes were attained: 91%, 90% and 89%, respectively, for whewellite; 99%, 98% and 99% for weddellite; 88%, 89% and 88% for uric acid; 91%, 89% and 90% for struvite; 99%, 99% and 99% for cystine; and 94%, 98% and 99% for brushite. Using deep-learning methods, the sensitivity, specificity and PPV for each of the classes were as follows: 99%, 98% and 97% for whewellite; 98%, 98% and 98% for weddellite; 97%, 98% and 98% for uric acid; 97%, 97% and 96% for struvite; 99%, 99% and 99% for cystine; and 94%, 97% and 98% for brushite. CONCLUSION: Endoscopic stone recognition is challenging, and few urologists have sufficient expertise to achieve a diagnosis performance comparable to morpho-constitutional analysis. This work is a proof of concept that artificial intelligence could be a solution, with promising results achieved for pure stones. Further studies on a larger panel of stones (pure and mixed) are needed to further develop these methods.

Speckle Noise Algorithm-Based Ultrasound Imaging in Evaluating the Therapeutic Effect of Blood Purification on Children with Kidney Failure and Analysis of Its Correlation with Serum Inflammatory Factor Levels.

The study focused on the therapeutic effect of clinical treatment on urinary calculi with kidney failure and its relationship with the serum inflammatory factor levels. 90 children with melamine urinary calculi were selected as research subjects. Of them, 52 cases were in group 1 (nonrenal failure), and 38 cases were in group 2 (combined with renal failure). In addition, 35 hospitalized children with no history of melamine-contaminated milk feeding during the same period were used as healthy controls. They all underwent ultrasound imaging examination based on the speckle noise algorithm, and the prognosis was analyzed. It was found that the peak signal-to-noise ratio (PSNR), structural similarity (SSIM), and local edge preservation index (EPI) of the algorithm in this study were significantly greater than other algorithms (P < 0.05). The admission age of the children in group 1 was significantly younger than that of group 2, the bilateral stone rate was significantly higher than that in group 2, and the difference was statistically significant (P < 0.05). Of the 52 children in group 1, the stone disappeared in 25 cases after treatment, the stone was reduced in 20 cases, and the stone remained unchanged in 7 cases. The total effective rate of treatment was 88.46%. Of the 38 cases in group 2, the stone disappeared in 22 cases after treatment, the stone was reduced in 12 cases, and the stone remained unchanged in 4 cases. The total effective rate of treatment was 89.47%. No difference was noted in blood urea nitrogen (BUN), blood creatinine (Cr), TNF-α, and C-reactive protein (CRP) levels in group 1, group 2, and the healthy control group (P > 0.05). Hence, the denoising algorithm in this study has better denoising effects on ultrasound images than traditional algorithms, with higher definition and less noise and artifacts. The clinical treatment of children with urinary calculi and renal failure is highly effective, the renal function and serum inflammatory factor levels return to the normal range, and the inflammatory response is weakened.

Twenty-four-hour Urine Testing and Urinary Stone Disease Recurrence in Veterans.

OBJECTIVE: To determine whether 24-hour urine testing in Veterans with USD (urinary stone disease) reduces or delays urinary stone recurrence. METHODS: Cohort study of national health record data from Veterans Health Administration from 2007 through 2013. We utilized a study population of 130,129 Veterans with USD based on diagnostic or procedural codes and excluded those with USD claims in the 2 years before cohort entry. We then created a propensity-score matched cohort of 14,854 Veterans based on completion of 24-hour urine testing within 6 months of stone diagnosis. Primary outcome was time-to-next clinically significant stone event, defined as an emergency department visit, inpatient admission related to a urinary stone, or urologic stone procedure with 5-year follow up. RESULTS: Of 14,854 Veterans in the propensity-score matched cohort, 8560 (57.6%) experienced a recurrent USD event. Completion of 24-hour urine testing was associated with a higher risk of developing a second stone event (hazard ratio [HR] 1.17, 95% confidence interval [95% CI] 1.12-1.22). Among Veterans with known recurrent disease, we examined time to a third stone event. In this cohort of 4736 patients, completion of 24-hour urine testing was not associated with a higher risk of developing a third stone event (HR 1.06, 95% CI 0.99-1.12). CONCLUSION: Completion of 24-hour urine testing was not associated with a reduction in urinary stone recurrence. These findings challenge the validity of a longstanding recommendation in general medicine, nephrology, and urology practice.

[Diagnostic possibilities of qualitative express analysis of mineralogical structure of urolites].

OBJECTIVE: the aim of the determination of the diagnostic information content of the qualitative analysis method - urinary calculus for use in medical practice in the study of the chemical structure of urolite. Materials, methods: Determination of the chemical composition of uroliths in the collection of urinary stones (n=2960), presented in "a Database of patients with urolithiasis who live in the territory of the Republic of Belarus" (2006-2019), made the developed method of qualitative analysisbased on the combined conduct of optical macroscopy of the sample, qualitative chemical reactions and chemical reactions of reprecipitation with subsequent microscopy of the crystals formed. RESULTS: The developed method allowed identifying the following clinically most significant mineral components of urinary stones: vevellite (42.4%), weddellite (28.1%), Apatite (19.6%), carbonate Apatite (5.1%), struvite (13.2%), uric acid (17.6%), ammonium urate (0.4%), cystine (0.7%). The obtained data were consistent with the results of studying the elemental composition of urinary stones (n=24) by atomic emission spectrometry with inductively coupled plasma. The calcium level was highest in calcium stones (25.56% C oxalate and 19.73% C phosphate) with a minimum content (0.012%) in urate stones. The amount of magnesium prevailed in the group with magnesium-ammonium-phosphate stones (2.51%) at extremely low concentrations in urate samples (7.810-4%). The percentage of phosphorus was maximum (13.47%) in the group of uroliths, represented by phosphate salts of calcium and magnesium (with values of 0.67% - calcium oxalate and 0.013% urate). Identification of trace elements Al, Ba, Cu, Fe, Zn, Sr revealed a fluctuation in their content in the range from 0.037 to 546.3 ppm. CONCLUSION: Considering the practical availability of implementation, low financial costs and sufficient information, the method of qualitative rapid analysis of urinary stone, based on a combined optical macroscopy of the sample, qualitative chemical reactions and chemical reactions of reindeposition with subsequent microscopy of the formed crystals, can be recommended for wide use in medical institutions of any regional level in the diagnosis of chemical types of uroliths in patients with ICD.

[Diagnosis and treatment of urinary stones: progress and prospect].

Although minimally invasive diagnosis and treatment technology for urinary stones has been widely developed, with continuous progress and cross integration of imaging, laser technology, endoscopic technology, and materials science, new diagnosis and treatment equipment emerge in endlessly, which promotes the continuous progress and innovation in diagnosis and treatment technology for urinary stones. By introducing the advances in imaging, lithotripsy tools, new endoscopes and ureteral stents, and analyzing their application prospects, it helps us understand the development trend of diagnosis and treatment of urinary stones in the future.

Qualitative Assessment of Medical Information on YouTube: A Multilingual Comparison of Common Urological Conditions.

INTRODUCTION: Patients nowadays often search video-sharing platforms for online patient education materials. Since previous assessments of urological videos were limited to English, we systematically assessed the quality of videos on treatment of benign prostatic hyperplasia (BPH), prostate cancer (PCa), and urinary stone disease (USD) in 4 different languages on YouTube using validated instruments. METHODS: The search for videos on YouTube addressing treatment options of BPH, PCa, and USD was performed in October 2020 in -English, French, German, and Italian. Assessed parameters included basic data (e.g., number of views), grade of misinformation, and reporting of conflicts of interest. Quality of content was analyzed using the validated DISCERN questionnaire. Data were analyzed using descriptive statistics. RESULTS: A total of 240 videos (60 videos in each language) were analyzed. Videos on USD in English had the highest number of views (median views 271,878 [65,313-2,513,007]). The median overall quality of videos assessed showed a moderate quality (2.5-3.4 points out of 5 points for DISCERN item 16). Median total DISCERN score of all videos divided by language showed very similar results: English (39.75 points), French (38 points), German (39.5 points), and Italian (39 points). Comparing the different diseases, videos about BPH showed the highest median scores, especially in German language (median score 43.25 points). CONCLUSIONS: Videos concerning the treatment of BPH, PCa, and USD have a low to moderate quality of content, with no differences seen between the languages assessed. These findings further support the notion of improved patient information materials on video platforms such as YouTube.

Comparison of retrograde intrarenal surgery and standard percutaneous nephrolithotomy for management of stones at ureteropelvic junction with high-grade hydronephrosis.

Percutaneous nephrostomy (PCNL) and retrograde intrarenal surgery (RIRS) are the two main treatments for upper urinary tract stones. The aim of our study was to compare the effectiveness and safety of standard PCNL (S-PCNL) and RIRS for the treatment of stones at ureteropelvic junction with high-grade hydronephrosis. The study included 118 patients who underwent surgery for stones at ureteropelvic junction. S-PCNL and RIRS were performed on 66 and 52 patients, respectively. Patient age, sex, body mass index (BMI), stone side, history of urinary tract infection (UTI), history of diabetes, history of ESWL, stone size, Hounsfield unit (HU) values of stones, grade of hydronephrosis, operating time, postoperative hemoglobin loss, narcotic analgesic use, postoperative transfusion rates, stone-free rates (SFRs), length of hospital stay, complication rates and number of secondary interventions were recorded. The comparison of the operative data between the two groups revealed no statistically significant differences in the operative time, SFRs, narcotic analgesic use, postoperative transfusion rate or other postoperative complications defined according to the Clavien system (P > 0.05). The postoperative urinary sepsis rate in the RIRS group was as high as 15.4%, which was much higher than the 1.5% rate observed in the S-PCNL group, and the difference was statistically significant (P < 0.05). A total of 13.5% of the patients in the RIRS group required a second operation due to failure of the placement of the ureteral access sheath. Additionally, S-PCNL had an advantage in operation time, while RIRS in duration of hospital stay and postoperative hemoglobin loss. RIRS and S-PCNL were safe and effective methods for the treatment of stones at ureteropelvic junction with high-grade hydronephrosis. Importantly, S-PCNL had more advantages in terms of the postoperative urinary sepsis rate and secondary surgery rate.